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Old 06-30-2022, 10:23 AM   #11 (permalink)
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taping over

Since the sub- Cd 0.17, M-B Vision EQXX has non-ventilated wheel covers, and low drag was of paramount concern to M-B, it implies that, like so many other 'record' vehicles: when you want really low drag, get as close as you can to MOON wheel covers.
One wind tunnel investigation by John Shinella of GM, specifically tested tape on the wheel covers of the 1982 Pontiac Firebird Trans Am. It registered the lowest drag of any configuration examined.
Renault, for their sub- Cd 0.19, 1987, Vesta-II concept, essentially 'taped' all but one opening in their wheel covers. It obviously took care of brake cooling, plus allowed for the valve stem access. Also, the actual opening on these covers were uni-directional in design. Something of interest to us.

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Old 06-30-2022, 01:32 PM   #12 (permalink)
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Old 06-30-2022, 01:50 PM   #13 (permalink)
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I don't want to go too far off topic, but I got this idea...
The main reason (other than looks, but this can be disputed) for NOT having fully covering moon-caps (and closing up from the inside and below) is brake ventilation.

So how about if there would be small flaps in the front bumper which would open each time the brake pedal would be pressed, scooping air from the front and channeling it onto the front wheels' brakes.

The flaps would mess up aero, but only during physical braking, so wouldn't impact FE.
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Old 06-30-2022, 01:57 PM   #14 (permalink)
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brake flap inlets

This sort of thing has already been proven at Bonneville in the streamliner class. In the 1930s if memory serves me.
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Old 06-30-2022, 02:07 PM   #15 (permalink)
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Quote:
The main reason (other than looks, but this can be disputed) for NOT having fully covering moon-caps (and closing up from the inside and below) is brake ventilation.
Access to the valve stem?
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Old 06-30-2022, 03:36 PM   #16 (permalink)
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Quote:
Originally Posted by freebeard View Post
Access to the valve stem?
Granted

But you access the valve only in a periodic, controlled way, and never when rolling.

So the access can be by removing or bending the cap, a removeable cover over the hole, etc.
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Old 06-30-2022, 05:19 PM   #17 (permalink)
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Quote:
Originally Posted by Piwoslaw View Post
The flaps would mess up aero, but only during physical braking, so wouldn't impact FE.
Messing up aero while braking could eventually improve braking, and decrease wear and tear of the brakes too. Not a bad idea at all, yet controlling the flaps may add a layer of complexity and weight...
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Old 06-30-2022, 05:34 PM   #18 (permalink)
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controlling

Quote:
Originally Posted by cRiPpLe_rOoStEr View Post
Messing up aero while braking could eventually improve braking, and decrease wear and tear of the brakes too. Not a bad idea at all, yet controlling the flaps may add a layer of complexity and weight...
The brake light circuit could be the trigger. It's enabled at all times.
Since rotors and drums have the facility to store quite a bit of heat flux, actual flap opening could be delayed on a timer, as well as the closure.
An interrogating remote infrared sensor, calibrated for open circuit threshold would initiate the end of the cooling cycle once rotor or drum temp. parameter was satisfied.
Low power 12-VDC solenoids could actuate the flaps against a mechanical spring preload and viscous damper.
Or wire them 'fail-open'.
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Old 06-30-2022, 09:33 PM   #19 (permalink)
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Update, regular duct tape doesn’t hold up well at 90 mph and head winds haha. May have to find some grey gorilla tape versus plain duct tape
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Old 06-30-2022, 10:44 PM   #20 (permalink)
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Hundred-mile-an-hour tape got it's name for some reason.

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